a) Description of the Related Art
The present invention is directed to a device for varying and adjusting the transmitted illumination for microscopes, particularly with respect to the numerous different illumination situations.
b) Description of the Related Art
Aside from conventional transmitted brightfield illumination which couples the more-or-less directed illumination light directly into the imaging system of microscopes via the object, solutions for implementing oblique illumination are also known from the prior art. In the simplest case, this oblique illumination can be realized by tilting and/or displacing a mirror used for beam deflection. It is possible to improve contrast by means of oblique and/or one-side illumination.
In the C-DSD 230 transmitted-light illuminator by Nikon, a diaphragm is displaced directly on a deflecting mirror for improved contrast. In many embodiment forms of transmitted illumination systems, it is possible to switch between different adapting optics in order to adapt simple transmitted brightfield illumination to different visual fields which chiefly depend on the adjusted magnification and on the objectives that are used.
In accordance with the user's wishes, the brightness should be adjustable, if possible, with preset desired color temperature. This is often carried out at separate cold light sources so as to avoid impermissible heating of the specimens and microscope.
In some transmitted illumination arrangements, it is possible to insert different filters and/or ground glass diffuser screens to achieve a diffuse illumination.
Further, transmitted darkfield illumination arrangements can be used as an alternative illumination method in modern illumination devices. In this case, the light of the illumination source is guided past the objective and only light that is scattered at the object, diffusely reflected light, interrupted and/or diffracted light is coupled into the objective.
A large number of operating elements are red to dust a particular illumination situation. This is especially true for modern transmitted illumination deices. An illumination situation that has been adjusted one time cannot be reproduced again or, if so, only with considerable effort. This is because intermediate positions must often be adjusted and the large number of operating elements makes this very complicated.
Some of the operating elements must be combined in a certain way to enable useful illumination conditions. These combinations must be adjusted manually by the user. Particularly users who seldom work with the microscope in question do not possess the required knowledge about useful combinations, and this knowledge cannot be acquired without considerable effort.
Further, the arrangement of operating elements is often disadvantageous in ergonomic respects. This poses another obstacle to ease of use and manageability. Further, the large number of moving operating elements renders the construction of the stand very costly. Stability must be maintained in spite of the many openings. Moreover, scattered light must be prevented from exiting and the penetration of liquid and dust must be prevented. Considerable construction resources must be expended to prevent the disadvantages effects mentioned above while maintaining the desired large range of operations of the transmitted illumination device, which makes manufacture extremely expensive.